Date of Award
Fall 2022
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Interdepartmental Neuroscience Program
First Advisor
Verhagen, Justus
Abstract
Animal survival in the wild is largely dependent on their ability to locate food sources, find mates, and avoid predators — tasks which are all heavily reliant on their sense of smell. However, to be adept at these behaviors, animals must navigate a complex odor landscape where odors cues can be released in many forms, including odor trails and airborne odor plumes. Odor plumes result when an odor is carried by ambient wind, where it’s structure changes with distance from the odor source, providing potential navigational cues to searching animals. Odor plumes can adopt a variety of structures depending on the odor landscape, such as pulled odor filaments that are interleaved with pockets of air in a turbulent environment. Due to advancements in fluid dynamics technology, allowing for the detailed measurement of airborne odor plumes, recent studies have begun to explore how odor plume properties affect olfactory search behavior in mammals. This dissertation seeks to advance the understanding of how changes in odor plume properties can guide navigation behavior and alter olfactory search strategies. In Chapter 2, we explore the effects of increasing odor plume complexity on the accuracy of odor source localization as well as navigation strategies in mice. In Chapter 3, we determine if odor intermittency can be used by mice to locate an odor source. Intermittency measures the fraction of time odor is present at a given point within the plume and decreases with increasing distance from the odor source. We test if mice can discriminate odor plume samples of low and high intermittency as well as explore how the neural encoding of intermittency in the olfactory bulb may enable intermittency discrimination. In Chapter 4, we explore the effects of sniff frequency, a behavioral parameter that is highly modulated during odor-guided navigation, on olfactory bulb representation of intermittency. Together, these studies demonstrate that intermittency is an odor plume property that can inform olfactory search, is encoded in early stages of olfactory processing within the olfactory bulb, and is subject to changes in representation based on active sampling strategies. More broadly, this work supports the notion that mammalian odor-based navigation depends on and can be guided by odor plume properties.
Recommended Citation
Gumaste, Ankita, "Influence of odor plume properties on behavioral decisions and odor representations in the mouse olfactory bulb" (2022). Yale Graduate School of Arts and Sciences Dissertations. 850.
https://elischolar.library.yale.edu/gsas_dissertations/850
